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Aug 22, 2016 The following will look at soil characteristics in greater detail. |
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Aug 22, 2016
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Aug 22, 2016 Soil is called backfill, if “it has been artificially placed”. Backfill is divided into:
[ [DIN1054:2010]], [[ASTM D2321–05]] (Image: Compacted backfill under a motorway) Most of the areas below the surface of traffic ways … |
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Aug 22, 2016 The following categories will be used for a more detailed description: (Image: Unconsolidated soil categories) |
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Aug 22, 2016 |
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Aug 22, 2016 The main types of soil are:
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Aug 22, 2016 By non-cohesive soil, the individual mineral or rock grains form a loose cluster as a result of frictional forces that occur when the grain surfaces rub against each other. The characteristics of non-cohesive soil are influenced by the following parameters:
(Image: Non-cohesive soil particles, held loosely together through the grain surface friction) Sands, gravels, stones and their … |
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Aug 22, 2016 In the case of cohesive soil, the particles cling together as a result of electrostatic surface forces, and thus form a bonded and mouldable mass. Its characteristics (strength) is essentially influenced by the following parameters:
This type of soil is sensitive to weather conditions. It includes clays, clayey silts (e.g. sandy clay, sandy silt, loam, marl) as well as their mixtures with non-cohesive … |
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Aug 22, 2016 The soil is classified as organic silt or organic clay if the liquid limit after oven drying is less than 75 % of the liquid limit of the original specimen determined before oven drying. A further classification of organic fine grained soils (group symbols OL and OH) is presented in a future section [[ASTM D2487-06]]. Another organic soil type is peat, that consists of "primarily vegetable tissue in various stages of decomposition usually with an … |
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Aug 22, 2016 The (top) soil in a narrow sense is defined as the most biologically active part of the top crust of the earth, which is surrpunded by rock or soil below, and by vegetation or atmosphere above [MURL1991]. The soil can be classified, based on its percent by mass, into organic soil and mineral soil with an organic percentage [ [DINENISO14688:2018] [DINENISO14688:2018]]. (Image: Topsoil) (Table: Classification of soil with organic percentages according … |
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Aug 22, 2016 According to [ [DINENISO14688:2018]], volcanic soil is defined as “magma that has been emitted into the atmosphere during intense volcanic eruptions and, over time has formed deposits; e.g. pumice, scoria, ash”. The main percentages of volcanic soils are designated and described according to their particle size, structure and colour (Table). (Table: Designation and description of volcanic types of soil [ENISO14688]) |
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Aug 22, 2016 |
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Aug 22, 2016
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Aug 22, 2016 The grain particle shape has an influence on the texture and isotropy of the soil, as well as on the structural characteristics of the subsoil, such as the frictional resistance, shear strength, water permeability, compactness- and displacement capability [Soos96] [Trian00]. (Image: Particle shape - well rounded) (Image: Particle shape - Rounded) (Image: Particle shape - Sub rounded) (Image: Particle shape - Angular) (Image: Particle shape - Very … |
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Aug 22, 2016 |
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Aug 22, 2016 The primary distinctive feature of mineral soil is the grain size of the individual particles. The determination of the grain size is the first step in the designation- and classification process of a certain type of soil. (Image: Soil grain sizes from 0 – 4 mm) (Image: Soil grain sizes from 4 – 25 mm) |
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Nov 02, 2016 An important factor in soil classification presented in the upcoming pages is the soil particle size (grain size). Two scales are used for classification purposes of soil grain size: the US Sieve Series and the Tyler Equivalent. The table below presents the most common sieve mesh opening sizes for these two scales is presented in the table below. (Table: US sieve mesh size) |
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Aug 22, 2016
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Aug 22, 2016
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Aug 22, 2016 The cumulative frequency polygon of the mass percentages of the given soil sample is called a grading curve (or grain size curve), and is used for a definite designation of the soil. (Image: Grading curves of some characteristic types of soil [Neuma64]) |
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Aug 22, 2016 (Image: Grain sizes classification) (Table: Soil characteristics) |
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Aug 22, 2016 Example: The measured values of the sedimentation analysis resulted in the following mass percentages: (Formula: Aus den Messwerten der Siebanalyse folgten die Gewichtsanteile) With ∑m (D < d) as the percent passing (percentage by weight) through the screen with the mesh size d and ∑ m(D) as the total mass of the sample. Consequently: (Formula: Gewichtsanteil y(0,063)) (Formula: Gewichtsanteil y(0,125)) (Formula: Gewichtsanteil y(0,25)) Table: Dry screening … |
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Aug 22, 2016
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Aug 22, 2016 |
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Aug 22, 2016 The grading curve results in essential curve parameters that require a prior determination of d10, d30 and d60.
By means of these details the curve parameters CU (coefficient of uniformity) and CC (coefficient of curvature) can be calculated to describe the … |
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